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Mark Wahlberg is in the highest domestic grossing film of his career, "Ted," but even he wasn't convinced at first that starring in a film with a life-sized talking bear was the best move for his career.

"It's ridiculous," he told ABCNews.com. "When somebody told me the idea, I said, 'Absolutely not.'

Finally he took a look at the script. "Thirty pages in you forget it's a teddy bear," said the star of "Boogie Nights," "The Departed," "Planet of the Apes" and "The Truth About Charlie." "I thought, this is one of the great buddy comedies. I met with Seth (MacFarlane, the film's writer and director and voice of Ted) and said, 'I'm in.'

Next he had to convince his wife, model Rhea Durham, that it was a good idea. They were in a limo on their way to the 2011 Academy Awards, where his film "The Fighter" was nominated for seven Oscars, when he described the premise of the movie. Her response: "That's going to end your career."

Of course, Wahlberg got the last laugh when Durham couldn't stop laughing at the first screening or talking about the movie afterward. "It's one of the few times, I told my wife, 'I told you so' without any repercussions."

Wahlberg spoke to ABCNews.com from a hotel room, where he was sitting with a talking "Ted," while promoting his latest film and latest business venture.

Known as much for his sculpted physique as his acting, Wahlberg recently teamed up with GNC to start Marked, his own nutrition line of supplements, protein powders and bars.

"I've always been into health and wellness, it's been a part of my life since I can remember," said the 41-year-old actor who once displayed his famous physique in a series of Calvin Klein ads. "I had no interest in endorsing products, though. I wanted my own business."

Wahlberg said after meeting with GNC's CEO Joe Fortunato, he sought out the best cutting edge science and highest quality ingredients to put together a series of products, none of which contain any banned substances.

The products are for everyone. "My wife is constantly stealing them," he said. "They're for young and aspiring athletes, people who want to get into shape and busy moms."

Don't expect to look like Wahlberg, though. The actor tries to work out five days a week and he's constantly adjusting his routine with his longtime trainer. After dropping down to 165 to play a detective in the upcoming political thriller "Broken City," he packed on the muscle, up to 205 pounds, to play a body builder in the recently wrapped "Pain & Gain."

"You can be the best you can be," he said. "You just have to work hard to get there."

Wahlberg hopes to help more people in the inner city live healthier lives by opening low-cost fitness centers, starting with his first one in Redondo Beach, Calif.

"This is the beginning," he said. "I'm very serious about it. I want people to be healthy and I want them to be able to have fun."

He's also sending a portion of all sales of Marked products to his foundation for inner city youth.

As for his other career - acting and producing - Wahlberg has some encouraging words for "Entourage" fans. He said the script for a big screen feature with your favorite fellas is about a month from being finished and he expects production to start in March.

He also said, despite his name being floated for the big screen adaptation of "Neuromancer," he has yet to see a script. But (note to the producers), he'd like to have a look.

Wahlberg recently responded to a backlash from ALS patients and advocates about a punchline from the movie "Ted." He told "The Tommy Show" on 94.7 Fresh FM radio in Washington, D.C., "Obviously, you know, it wasn't our intention to really offend anybody," said Wahlberg, who later agreed the film, written by "Family Guy" creator MacFarlane, offended people "across the board." "Seth wrote the material, so you've got to take it up with him."